Conventionally, as disclosed in Japanese Patent Application Laid-open No. H9-156528, there has been known a vehicle-operation assisting device that detects an advancing-direction azimuth angle of a vehicle and a tangential-direction azimuth angle of a road on which the vehicle travels and generates a steering torque in an orientation toward which a deviation between the detected advancing-direction azimuth angle and tangential-direction azimuth angle is decreased, thereby generating a steering force in a direction in which the vehicle is not departed from the road.
The conventional vehicle-operation assisting device is configured to output steering control based only on a deviation between the advancing-direction azimuth angle and the tangential-direction azimuth angle at a control point, without regard to a state of the vehicle operation of a driver and an environment on a periphery of the vehicle. Thus, according to the conventional vehicle-operation assisting device, steering control not suitable for the state of the vehicle operation of a driver (driving intension) and the environment on a periphery of the vehicle is outputted. This sometimes makes a driver feel a sense of discomfort or inconvenience for the steering control.